48. Which system represents the part of the autonomic nervous system that decreases breathing and heart rate?
Answer: C
The system that decreases breathing and heart rate is the Parasympathetic nervous system.
The Parasympathetic nervous system is responsible for promoting a state of rest and relaxation in the body, which includes decreasing both breathing and heart rate.
A) Sympathetic nervous system
The Sympathetic nervous system is associated with the body's 'fight or flight' response, which increases heart rate and breathing to prepare the body for action. Therefore, it does not represent a system that decreases these functions.
B) Somatic nervous system
The Somatic nervous system controls voluntary movements and the reflex arcs associated with skeletal muscles. It does not regulate involuntary functions such as heart rate and breathing, making it incorrect in this context.
C) Parasympathetic nervous system
The Parasympathetic nervous system plays a crucial role in conserving energy by slowing down the heart rate and increasing intestinal and gland activity. This directly correlates with the functions described in the question, making it the correct answer.
D) Central nervous system
The Central nervous system, which includes the brain and spinal cord, acts as the control center for processing information and coordinating activity throughout the body. While it influences both the sympathetic and parasympathetic systems, it does not directly decrease heart rate and breathing.
Conclusion
The Parasympathetic nervous system is definitively the correct answer because it specifically functions to decrease heart rate and breathing, promoting relaxation. The other options either increase these functions or do not regulate them, thus failing to meet the criteria of the question.